The 2nd and 3rd tiers when grouping reports does not work (at least in my case). The 1st tier is a Date by Month and this seems to work ok
The 2nd tier is location, but they are not getting grouped together. It is almost like they are being listed by day instead of by the month. If I remove the 1st tier and group only by location the system groups correctly. I'm am using build 305
I wasn't able to reproduce this error. Please publish your project on Demo Account and send to [email=support@xlinesoft.com]support@xlinesoft.com[/email] a URL to your pages along with instructions on reproducing this error.
I'll find what's wrong with your project inspecting it at Demo account site.